The problem SmartSplit solves

Splitting shared expenses is still mostly manual. One person pays the full bill, calculates everyone's share, tracks down wallet addresses, and chases each participant individually. The result is delayed payments, calculation errors, and no clear view of who's actually settled up.

SmartSplit turns this into a single coordinated, non-custodial payment workflow on Sui. Users connect their wallet, select friends or a saved community, resolve recipients by SuiNS name instead of raw addresses, attach a receipt, and choose an equal or custom split. One approved transaction then pays every recipient atomically. For cases where someone has already covered the full bill themselves, SmartSplit also supports payment requests, so the flow works whether the group is paying together upfront or reconciling after the fact.

Challenges we ran into

Designing around Sui's wallet-controlled transaction model. The frontend needs to calculate each recipient's share, split the payer's coin, construct the multi-transfer transaction, hand it off for wallet approval, and wait for on-chain indexing, all without SmartSplit ever holding custody of user funds at any step.

Coordinating the real-world layer around the payment. The on-chain transfer is only part of the problem. We also had to build friend and community management, payment requests, user profiles, SuiNS resolution, and a way to keep off-chain request status in sync with what's actually confirmed on-chain.

Receipt handling. We combined browser-based OCR with decentralized Walrus storage for receipt images, while making sure the detected amount is always shown to the user for verification or correction before they ever sign a transaction. Accuracy has to come before convenience here.

Validation and rounding. Equal and custom splits both needed clear validation to catch invalid or incomplete distributions before they reach the chain, along with correct rounding and dust handling, all while keeping the experience approachable for users who may have never used a crypto wallet before.